


The Brains Behind the Mask

by Ookami82



Series: hopeful existance [2]
Category: Teenage Mutant Ninja Turtles - All Media Types
Genre: Anatomy, Awkward Sexual Situations, Brotherhood, Gen, Medicine, Psychology, Science, Young Turtles
Language: English
Status: Completed
Published: 2015-01-27
Updated: 2015-01-27
Packaged: 2018-03-09 06:50:13
Rating: Mature
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 2,892
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/3240290
Author URL: https://archiveofourown.org/users/Ookami82/pseuds/Ookami82
Summary: <blockquote class="userstuff">
              <p>A side note to my Human Traits fic, all about Donatello's thoughts and muses regarding their existence...</p>
            </blockquote>





	The Brains Behind the Mask

**Author's Note:**

> Note: This story takes place in my "Human Traits" verse. You may want to use that as a reference, but it's needed to read this. Donatello is 17 at the time of this little story. Leo is 18, Mikey is 16 and Raph is 17. Take place after Leo's leave for Central America and probably during Leo's secret relationship.  
> Warning: there is some detail about the brother’s anatomy and thoughts about females in general. But it is told most in a medical-theory aspect.

Sometime 2012

Donatello is known to be the tallest, lankiest and most passive of his brothers. He is younger (by a year) than Raphael, but a year older than Michelangelo. He looked up to Leonardo, and secretly envied Raph for his rebelliousness for life in general. Donnie was also known to be snarky and sassy, but calm and non-judgmental as well. Unlike Leo, he was willing to share parts of his life, and communicate with others if he needed. But there were times where Donnie retreated into his own little world, often untouchable. He wielded the Bo staff with fierce intensity and grace. Like all of his brothers, he too was a master of the shadows, a ninja.

Donnie more importantly was the most intelligent member of the Hamato clan. He excelled in his schooling, never receiving anything below A, especially in math and science. The brothers had been taught a strict, basic curriculum by Master Splinter until they reached 13 years old, when they peaked in their ninjutsu abilities. But for Donnie, the things he learned were never enough. He found text books, upon textbooks in the sewers, dumpsters and junk yard. He taught himself algebra, geometry, calculus, chemistry, physics and biology. Most of those disciplines he probably knew at the graduate level by the time he was a teen. He had single handedly made their home in the sewers more comfortable than some humans. He rigged hot water, heat and electricity at a mere 8 years old, it was rudimentary but it worked. He installed cable at 10 years old and a working telephone a year later. Donnie built all his brothers (and his computers/ laptops from scratch. Their home even had Wi-Fi.

As he and his brothers grew older and technology advanced, Donnie made sure that his family had almost up-to-date TV’s, PlayStation, and tablets. He was rather fond of apple products and Beats headphones. When he turned 17 he got a job as an IT for a small company and made a fair amount of money the year his older brother trained on South America. And today he still worked for that same company making twice as much.

However there was a pivotal point in Donnie's life when he truly questioned who he and his brothers were-how they were made and how much similar they truly were to the humans they hid from. This was also the point in which, Leo, their fearless leader appointed him something far more important than his own status, the family doctor of his brothers and father.

_Flash back_

_Fall 2004_

_A 10 year old Leo barged into Donnie's room with a scowl on his features that a mother of 3 would be proud of. Donnie looked up from his text book, from his semi-prone form on his bed. He already knew what Leo was going to ask him before Leo spoke a word. It was always about the hotheaded and stubborn brother in red, Raphael._

_"Donnie, have seen Raph?" Leo asked quickly._

_Donnie pushed his glasses up on his snout. "No. I haven't seen him all day. Honestly Leo, I have been up here most of the day. I am learning calculus 1 by the title of this book. Did you ask Mikey? Maybe he knows considering he annoys Raphie the most."_

_Leo folded his arms across his chest. "I already asked. Mikey hasn't seen him since lunch. Master splinter hasn't seen him either. He thought he was in his room he's not, and we have to train in a half an hour! Why does he always do this?" Leo asked, clearly annoyed by his brothers frequent disappearances._

_Donnie knew the answer-they all knew where Raph ventured off to. Raphael loved going to the surface. He loved the sun and the wind and more significantly the trouble. Splinter had punished him time and time again, but that did not stop Raphael from doing what he wanted. Even just appointed leader, Leo knew this was going to be a constant problem he would face and desperately wanted a way to solve it. They were only getting older and Raphael's temper was starting to really flare. Splinter had told them would all start changing now that they were reaching double digits, and Raph was no exception. He always had issues listening to authority. It probably made things worse that Leo was appointed leader and not himself. Regardless of Raph’s feelings, Leo wanted no beef between him and his other brother._

_"He'll come back Leo. He always does, besides we have dinner after training. Master is making Italian! Spaghetti, Raph wouldn't miss that for the world. We got lucky this week dumpster diving. “Donnie smiled with his gap ever present. His adult Teeth had grown in and the gap came with it._

_Leo still frowned. "He's gonna get himself into serious trouble one day, I swear. I am going to tell master I have to go get him and get Mikey to help me look for him. Can you sit in the den, in case I need to call."_

_"Sure Leo. Make sure you and Mikey dress warm the temperature is going to drop today." Of course Donnie knew the weather report._

_It wasn't until a half an hour later, Leo and Mikey came with Raph in between them with frightened looks on their faces. They took Raphael straight up to his room. Donnie did not miss all the blood on Raph’s right ankle._

_Donnie jumped from the couch and followed his brothers, grabbing the first aid kit along the way._

_Donnie went into the room where voices harshly whispered. Raph looked pale and shaken. Mikey looked as if he was going to cry. And Leo looked beyond pissed._

_"What were you thinking!?" Leo harped at the second oldest brother. "And what am I supposed to tell Master!? I can't tell him you got bitten by a dog! Then we will all be in trouble, mostly me- I’ll be in trouble for not watching you." Leo finally simmered down._

_"Whatever Leo! You can tell him whatever the heck you want. I was helping that kid, y’know…and he was way younger than me! You’d think you would be thankin’ me, not lecturin’ me! God! Ya couldn't stand to get in trouble. You’re such a teacher’s pet!" Raphael bickered back._

_Leo was good enough not to take the bait and noticed Donnie standing in the door way. "That's not the point right now. You got bitten by dog! And it could get infected...or worse you could have rabies! We don't have that kind of medicine down here Raph! Tell him Donnie!" Leo pointed at Donnie. Donnie and came into the room to assess the damage of his brothers ankle. He knew very little about medicine, just the basics; cleaning wounds, and wrappings._

_"Well, Leo is right about the rabies. But dogs have pretty clean mouths, so chance of an infection is small, but probably still possible. I mean we do live and walk around the sewers. But I don't know much about..." Donnie lifted the towel that is brothers had hastily wrapped the ankle with. The wound was 2 deep punctures, jagged and crusty. There was noticeable dirt and debris in the wounds._

_"... Deep wounds like this." he finished quietly. He suddenly felt unsure and quite nauseous. He was only 9 years old for crying out loud, not a doctor!_

_"I'll clean it as best as I can, but Leo… I need to do some research on this. None of us have ever had a wound this bad before. Just cuts and stuff…and Splinter took care of that. We might have a problem if it gets infected."_

_"Is he gonna die?!" Mikey suddenly spoke almost at a whisper, tears willing to fall at any moment. He had been terribly quiet throughout the ordeal. Donnie suspected Mikey was not keen about blood and injury, like himself._

_Raph snorted and swiped his little brother across the back of his head. "I ain’t gonna  die stupid!" He barked and then looked to Donnie, who was always expected to have answers. “Right Donnie?"_

_Donnie took a little breath in. "I don't think so...but I really don't know. I haven't studied anatomy yet. Cellular topics are covered in biology, not stuff like this." He pointed to Raph’s ankle. "Like I said I have to research this."_

_Leo put his game face and on. He looked at Mikey first. "Mikey get master splinter and tell him We can’t come and train right now…tell him Raph is sick. And DON’T tell him Raph got bitten by a dog, got it?"_

_"Yeah, uh.... I won't... I swear. On it now." Mikey fled from the room. Probably glad to get away from what he considered gore. Leo turned back to Donnie and Raph._

_"Donnie clean that as best as you can. I'll be back in a bit." he directed at Donnie who was already scrubbing the dirt from the puncture marks._

_"What, are you our mother now, Leo? Barking orders at us already. It’s not the end of the world if we don’t train." Raph cut in and winced when Donnie touched his wounds._

_Leo sighed. "No Raphael. I am the leader now, and I say we need to fix you up real quick so we all don't get in trouble. It’s bad enough you ventured out and didn’t tell anyone, that you went to the surface and risked our safely. The least you could do is thank me and Donnie, because we havet to cover for you."_

_It was 3 days later that Raph was trying to hide his limp during training, when Donnie realized that he needed to take another look at his leg. Master splinter was told later (after he had been “sick”) that Raph had cut his ankle on a nail._

_Donnie along with Leo went into their brother’s room that night to find that Raphael's leg was badly infected. It was red, raw and draining pus. Raphael could hardly stand on it, let alone allow any one touch it._

_"Leo… what are we going do?" Donnie asked quietly outside Raph’s room. “That’s really infected…an’ I think Raph might have a fever.” Donnie might have been the smartest, but Leo was the planner. He could make a plan in a blink of an eye._

_"I was going to ask you that...maybe we should tell master...maybe he'll know what to do...." But this time Leo was clueless. Donnie had to think of something fast._

_Donnie put a finger to his chin for a moment. "No Leo, I don't think is a good idea...I mean, Sensei doesn't really know much about serious medical stuff. I did do a little research last night. He might need medicine...something called an antibiotic."_

_What Leo didn't know was that Donnie was aware of the punishments Leo would endure if his brothers failed to behave. The father was a good man, but extremely strict when it came to his sons. Failure was considered dishonorable. Leo was well aware of how strict their Master was. He had been forced to train for 12 hours with no meal break, when Raphael climbed up to a crate and nearly caused a cave in. Or another time Leo was backhanded for letting Mikey have more than his share of cookies._

_"Can we buy that somewhere?" Leo asked, hopeful. Donnie blinked, brought back from his thoughts._

_Donnie Frowned. "No... I think a doctor has to write a slip for it. We can't go to a human pharmacy or a doctor...we have to think of something. I read that infections can get into your blood and make you really sick."_

_Leo thought for a moment before he sighed and his shoulders sank. "I hate to even consider this Donnie...but we might have to steal it. We can look up pharmacies in the yellow pages; try to find a small one close. You got that computer running right? Maybe you can hack into the security system….I have some money saved, we could leave there to pay for the medicine. It wouldn’t really be stealing them right?” Leo was only trying to appease himself at this point. “In the meantime, I think it would be wise if you started really studying medical stuff, something tells me we are going to need it in the future, and you are the one who's...uh the science guy. So from this day on, you’ll be our doctor. I expect you to learn all that you can. You are so important to our team, Donnie. "_

_(End flashback)_

It was then all those years back that Donnie learned about their unique make up and how to treat any medical issues they would come in contact with. He read _Merecks Medical manual, Greys Anatomy,_ and any other text that pertained to medicine. He learned of all the classes of human drugs and when they were used for, how they reacted with the body and even trialed the left over antibiotic on Splinter when he contacted Pneumonia one winter. When Donnie turned 12 he found an old x ray machine at the junk yard, he was able to fix it after a few short months. It was a little while after that he had to use it on Raph who had sprained his wrist while getting too worked up when sparring Leo. At that point he x rayed his brothers whole body and was fascinated by the results. He later met a retired cardiologist during an IT Call. The cardiologist still worked 2 days a week. They became friends and Donnie was able to get useful information and prescriptions he needed.

Donnie recalled that their once human Master had picked them up prior to him mutating. The human DNA on his hands mingled with theirs and when they mutated, they became much more human, than turtle. He learned that all their organs were arranged like that of a human. They had 12 ribs and vertebrae. They only difference was that their shells were fused to their backbone. They had the same carpels and metacarpals as humans, just less fingers and toes. Their brains were also structured like that of a human, including the cerebellum, cerebrum and medulla along with the gyrus that made the brain appear “crinkled”. The almost had the same number of bones as a human. They had all the muscle groups, expept some of the muscles located in the human back; in which their shells covered. They were almost as warmed blooded as humans, with an average oral temperature of 95.3. They were like hybrids of the 2 species.

He also learned they had shared their human counterpart’s male anatomy. They of course were bigger, thicker and a different color. Their testicles were inside of their bodies; however they produced sperm that looked very much human under the microscope. Donnie would never truly admit how he got his specimen! The form of their penis looked like a circumcised male, however, the organ did unsheathe from their tales and was lubricated. They had an anus as well; not cloacae like their animal equivalent. 

They matured physiologically, socially and psychologically like teen males. Donnie never forgotten the time when Leo had just turned 13 and he was barking an order at Raph during a few laps around the sewers (who stubbornly refused of course) and his voice cracked and squeaked like that of a girl. They all toppled over its laughter, while poor Leo was red-faced and embarrassed. Even Raph chuckled at the situation, though he was short to follow his older brother. It was also that time when the two oldest took longer showers and bathroom breaks. They secluded themselves to their rooms for long, extended period of times. Raphael found playboys and started a collection. They became interested in females, human females. Even Mikey seemed interested when he turned 12, Donnie was last to comprehend what his brothers found so fascinating, and oh was it fascinating!  But Donnie liked a certain female to be precise, not some pin-up blond with size DD cups. He liked April, sweet, smart and fun April. Years later Donnie knew it was just a teenage crush. When he commandeered a newer computer, he began his persuit of online chatting and blogging with human females (and not surpassingly Michelangelo did a well.)

Donnie later wonder if it was possible to impregnate a female. He was not able to find any significant results with any of his research. And when he found out Leonardo and Karai had done the deed several times, he knew it was very unlikely. But he found that their existence was both amazing and a curse. They were ridiculously human, but unable to live with humans. This effected Raphael most of all, as he became more violent, moody and terse as the years passed. It was no thanks to Raphael that Donatello became their family physician. Raph had more injuries and scars then the rest of them combined. Donnie had truly believed the words Leo told him. _“You are so important to our team, Donnie.”_ But when Leo was sent away, Donnie felt the complete opposite. He wasn’t any Leader like Leonardo; He was a man of science-A Doctor.

Fin

 

**Author's Note:**

> I really feel like I could have done better...but even still I enjoyed writing it:)


End file.
